Consolidation related utilities and offerings
General consolidation tools and Services
Microsoft Consulting Services, Microsoft Services QuickPlan and Microsoft Services Portfolio offerings for Server Consolidation solutions
Asset Optimization Group (AOG) CapacityPlanner is an agentless tool that gathers inventory and performance data, correlates this data to create server load profiles, and then provides server consolidation modeling. For mixed workload consolidation projects, the collected information helps you identify servers that can be consolidated (from a capacity perspective), eliminated, or reused. The information also helps you determine the capacity you will need for the new consolidated server.
Unisys Sentinel, You can use Unisys Sentinel solutions throughout the mixed workload consolidation life cycle for processes such as discovering, inventorying, and evaluating consolidation candidates. You can also use it to configure, migrate, and manage consolidated assets. These tools are available via Unisys Consulting Services.
Application or Server specific tools
The MOM 2005 Sizer provides recommendations for MOM server configurations based on modeled workloads. Recommendations include the CPU, memory, disk, and network bandwidth resources required to manage your environment. The sizer combines information you input about your environment with performance and scalability models of the MOM server architecture established in the MOM Performance labs. The output helps you plan the deployment of MOM 2005 management servers, database servers, and reporting database servers.
I'm sure there are many more, please let me know what I have missed but adding a comment.